net.twisterrob.gradle.vcs.svn.SvnPluginExtension.kt Maven / Gradle / Ivy

package net.twisterrob.gradle.vcs.svn

import net.twisterrob.gradle.vcs.VCSExtension
import org.gradle.api.Project
import org.gradle.api.file.Directory
import org.gradle.api.file.FileCollection
import org.tmatesoft.svn.cli.SVN
import org.tmatesoft.svn.core.SVNException
import org.tmatesoft.svn.core.internal.wc.SVNFileUtil
import org.tmatesoft.svn.core.wc.ISVNOptions
import org.tmatesoft.svn.core.wc.SVNClientManager
import org.tmatesoft.svn.core.wc.SVNStatus
import org.tmatesoft.svn.core.wc.SVNWCUtil
import java.io.ByteArrayOutputStream
import java.io.PrintStream
import java.security.Permission

@Suppress("detekt.UnnecessaryAbstractClass") // Gradle convention.
abstract class SvnPluginExtension(
	private val rootDir: Directory
) : VCSExtension {

	// Same as: new XmlSlurper().parseText(SVN.cli('info', '--xml')).entry.commit.@revision
	override val revisionNumber: Int
		get() = open().revision.number.toInt()

	override val revision: String
		get() = revisionNumber.toString()

	override val isAvailableQuick: Boolean
		get() = rootDir.dir(SVNFileUtil.getAdminDirectoryName()).asFile.exists()

	// Same as 'svn info'.execute([], project.rootDir).waitFor() == 0
	override val isAvailable: Boolean
		get() =
			try {
				open().isVersioned
			} catch (ignore: SVNException) {
				false
			}

	override fun files(project: Project): FileCollection =
		project.files(
			rootDir.file(".svn/wc.db"),
		)

	private fun open(): SVNStatus {
		val options: ISVNOptions = SVNWCUtil.createDefaultOptions(true)
		val clientManager = SVNClientManager.newInstance(options)
		val statusClient = clientManager.statusClient
		return statusClient.doStatus(rootDir.asFile, false)
	}

	// key method/closure - used as: def out = doSvnMain( 'your', 'svn', 'args', 'go', 'here' );
	@Suppress("unused")
	private fun cli(vararg svnArgs: String): String =
		captureSystemOut {
			preventExit { SVN.main(svnArgs) }
		}

	companion object {

		internal const val NAME: String = "svn"

		@Suppress("DEPRECATION") // TODEL if there's a replacement in https://bugs.openjdk.org/browse/JDK-8199704.
		private inline fun  preventExit(block: () -> T): T {
			val oldSecurityManager = System.getSecurityManager()
			System.setSecurityManager(NonExitingSecurityManager) // stop SVN.main from doing a System.exit call
			try {
				return block()
			} finally {
				System.setSecurityManager(oldSecurityManager)
			}
		}

		private inline fun captureSystemOut(block: () -> Unit): String {
			val baos = ByteArrayOutputStream()
			val oldSystemOut = System.out
			System.setOut(PrintStream(baos))
			try {
				block()
				System.out.flush()
				return baos.toString()
			} finally {
				System.setOut(oldSystemOut)
			}
		}
	}

	private object NonExitingSecurityManager : @Suppress("DEPRECATION") SecurityManager() {

		override fun checkPermission(perm: Permission) {
			// Do nothing, allow it.
		}

		override fun checkExit(status: Int) {
			throw SecurityException() // Prevent it.
		}
	}
}